@article{MM2_1992__75_4_155712,
     author = {G. Fang and N. Choussoub},
     title = {Second order information on {Palais-smale} sequences in the mountain pass theorem.},
     journal = {Manuscripta mathematica},
     pages = {81--96},
     publisher = {mathdoc},
     volume = {75},
     number = {4},
     year = {1992},
     url = {http://geodesic.mathdoc.fr/item/MM2_1992__75_4_155712/}
}